Integration of 3D Burial History and Calibrated Sandstone Diagenesis Models for Mapping of Reservoir Properties

T.R. Taylor¹, M.R. Giles², G.S. Yardley³, G.V. Birbiglia⁴, R.L. Lander⁵, and L.M. Bonnell^5
1Shell International Exploration and Production, Houston, Texas USA
²Shell International Exploration and Production, Rijswijk, The Netherlands
³Shell UK Exploration and Production, Aberdeen, UK
⁴Sarawak Shell Bhd, Lutong
⁵Geocosm LLC, Austin, Texas USA

An understanding of the three dimensional distribution of sandstone reservoir properties on a regional, prospect, or field development scale is necessary for petrophysical rock properties models, quantitative seismic interpretation, volumetric calculations, and well placement strategies. Numerical forward models (e.g. Touchstone) can be used to forecast the effects of compaction and quartz cementation on the evolution of sandstone porosity and permeability. Model calibration requires a rigorous and detailed approach to sedimentary petrology and basin modeling. Quantitative petrographic and core analysis data form the foundation for calibration of model parameters. These models provide probabilistic predictions of reservoir quality for a specific point in the subsurface as a function of temperature and vertical effective stress histories. In order to directly link reservoir quality predictions to 3D burial histories while maintaining the rigorous standards for Touchstone model calibration, a reservoir quality module (ResQ) was created for inclusion within Cauldron, Shell’s proprietary basin modeling software. ResQ contains the Touchstone calculation engine and runs in the 3D Cauldron environment. The calibration of model parameters is performed within Touchstone by sedimentary petrologists with appropriate expertise and exported to ResQ. Monte Carlo facilities within ResQ allow for statistical assessment of predicted values arising from the likely natural variability in sandstone composition and texture. The results of ResQ calculations are exported as 3D maps of potential porosity, permeability, and quartz cement. When coupled with depositional models, this workflow represents a major step forward in the application of burial history-based reservoir quality and rock property models. A number of integrated applications are envisioned, including; 1) evaluating the impact of alternative burial history scenarios on reservoir quality for prospect risking, 2) comparing reservoir quality trends for sands of varying composition and texture (tied to regional geology, depositional models/seismic facies, etc), and 3) assessing aquifer permeability in the absence of well control.

AAPG Search and Discover Article #90066©2007 AAPG Hedberg Conference, The Hague, The Netherlands